Baltimore Ravens linebacker Brendon Ayanbadejo has been encouraged by all those who applaud his support of gay marriage. / Nick Wass AP

by Brendon Ayanbadejo, USA TODAY

by Brendon Ayanbadejo, USA TODAY

The trailer for the upcoming film "42" begins with a silhouetted baseball player walking down the tunnel toward the dugout. A voice says: "I don't know who he is, or where he is, but he's coming." The scene captures the anticipation of Jackie Robinson crossing the Major League Baseball color barrier. That moment just before history is made is a moment that sure feels a lot like now, as we wait for the arrival of the first openly gay man in U.S. major professional team sports.

Just like Jackie, the breakthrough gay athlete will be a courageous individual going it alone in uncharted territory. But, also like Jackie, he will have backup -- and hopefully more of it.

One of the seminal moments of Jackie Robinson's first season with the Brooklyn Dodgers was when teammate Pee Wee Reese put his arm around Jackie during a game and then faced the crowd. The message was clear: teammates are teammates. Brothers. Reese wasn't a civil rights advocate. But he wasn't merely a good guy either. Reese was exactly what the codes of sportsmanship expected him to be, someone who knew what was right and did it despite the risks. Simply put, he was an ally.

I know that there are plenty of good men in the NFL. I am fortunate to play alongside them as a member of the Super Bowl XLVII champion Baltimore Ravens. Together the Ravens became world champions. Together we can be more than Super Bowl winners. Together athletes in all four of our country's major sports leagues -- the NFL, MLB, NHL and NBA -- can be more than good men. Since human rights are far more important than sports, we need to be Athlete Allies who are willing to leverage our social capital and all that goes with it -- like fans, endorsement deals and more -- to stand up for a larger purpose.

That's why I began advocating for marriage equality four years ago. As the child of a Nigerian dad and Irish-American mom, I was raised to believe that, in America, our differences don't matter and discrimination is wrong. During my career in the NFL, I've watched LGBT Americans struggle to make gains in legislatures, schools and boardrooms around the country. Since I first signed with the Falcons in 1999, Wall Street and corporate America have worked to create internal departments and networks focused on LGBT diversity and inclusion. The largest companies in the world have signed on to legal briefs in support of marriage rights for same-sex couples and CEOs have publicly spoken out for LGBT rights. What's even more inspiring is that, after decades of discrimination against gay and lesbian members of the United States military, President Obama ended "don't ask, don't tell." The president made history again in his inaugural address, when he called for equal rights for gay and lesbian Americans -- including the right to marry whomever they love.

With these successes piling up and progress on the rise, an issue closer to home comes more sharply in focus: the sports world -- my world -- is the last closet in America.

There are many reasons why no gay athlete has come out in the NFL, NBA, NHL or MLB, most of which are likely to go away with support and acceptance from the straight community. As leaders and even role models for millions of young people across the globe, professional athletes have the ability to fundamentally eliminate prejudice from our sport and live up to the incredible privilege we enjoy.

At its best, sports do not discriminate. If you are young or old, tall or short, male or female, gay or straight, all that really matters is how well you play and contribute to your team.

The NFL, MLB, NHL and NBA should and can be leaders against discrimination. Whether you're a commissioner, an athlete, a coach or a fan, your voice will let every kid out there know that there is a place for him or her in sports. We all can be ourselves and still compete with dignity and at the highest level.

This is our time and our cause. Everything we know as athletes, teammates, spokesmen and vehicles of American pastimes compels us toward the kind of action and camaraderie we saw from Pee Wee Reese nearly 66 years ago. It's as simple as putting our arm around the shoulder of another athlete. It's a gesture; it's a pledge; it's solidarity at its most basic. Our Jackie is coming. We need to pave the way.

Brendon Ayanbadejo is a linebacker for the Super Bowl champion Baltimore Ravens and an ambassador for Athlete Ally, a non-profit organization committed to ending homophobia in sports.

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